This invention relates to telecommunications devices and, more particularly, to an improved transceiver operable in both the cellular and PCS frequency bands.
In recent years, portable handheld wireless communications devices have become increasingly popular. At the present time, cellular telephones operating in the frequency band of about 824 MHz through about 894 MHz are the most widespread type of such devices. However, the personal communications system (PCS) operating in the frequency band of about 1850 MHz through about 1990 MHz is gaining in popularity. Accordingly, equipment suppliers are developing portable handheld radio transceivers which operate in both these frequency bands. Thus, there exists a need for a transceiver capable of operating in both of the described frequency bands.
It would appear to be a fairly straightforward task to construct such a transceiver wherein signals in the two bands are carried over separate paths within the transceiver. However, such a design would result in a duplication of much of the circuitry. Accordingly, there exists a need for a transceiver capable of operating in both of the described frequency bands in which much of the signal processing circuitry for the two bands is shared, to provide a more cost effective transceiver construction.